package com.itheima.reggie.filter;

import com.alibaba.druid.sql.visitor.functions.If;
import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否登录
 */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器支持通配符
    public static final AntPathMatcher PATH_MATCHER =new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //获取本次请求的url
        String requestURI = request.getRequestURI();
        log.info("本次拦截的路径:{}",requestURI);

        //定义不需要处理的请求路径
       String[] urls = new String[]{
               "/employee/login",
               "/employee/logout",
               "/backend/**",
               "/front/**",
               "/common/**",
               "/user/sendMsg",
               "/user/login"
       };

       //判断本次请求是否需要处理
        boolean check = check(urls,requestURI);
        //如果不需要处理直接放行
        if (check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //判断登录状态如果已登录放行
        if (request.getSession().getAttribute("employee") !=null){
            log.info("用户已登录,id为{}",request.getSession().getAttribute("employee"));

            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);
            return;
        }

        if (request.getSession().getAttribute("user") != null){

            log.info("用户已登录，用户id为：{}",request.getSession().getAttribute("user"));

            Long userId= (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        //5、如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /**
     * 检查本次是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    private boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url,requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
